Opposites Attract

"Strange extremes meet in love's pathway."

—The Scarlet Pimpernel

Strong relationships, in both TV and real life, thrive on how each member compensates for the other’s weaknesses with his/her own strengths, and vice versa.

A Motor Mouth just isn’t as funny if he doesn’t have the Straight Man to torment. Similarly, only when a sweet, shy person is paired up with an equally jerkish one is their kindness and timidness made all the more noticeable.

It is all but guaranteed that the characters’ differences will cause more friction than harmony between them. That’s what gives the Odd Couple its fuel for Slap Slap Kiss, Will They or Won't They?, and Aw, Look -- They Really Do Love Each Other situations. Bickering and mushiness in one package. What’s not to like?

The Odd Friendship also has elements of this, but tends to focus on how the differences make them see each other, and maybe the world, through new eyes. Perhaps the serious one is Not So Above It All, or the Shrinking Violet has an inner strength she never knew she had. A Moe Couplet also does something similar to this, focusing on how each half of the couplet brings out the other's endearing or nurturing traits.

Opposites Attract has become so widespread in buddy cop shows, in the form of Serious White Guy meets Loud Black Guy, that it branched off into its own subtrope.

About the biggest challenge in creating a day-and-night dynamic is to keep the attract and repel cases relatively balanced. When the pendulum swings too far toward the repel side and the characters seem more interested in torturing each other than helping out, it’s no longer cute to watch; it’s just masochistic. The key (both in fiction and in Real Life) is to watch the pair's goals. If they want the same thing but use completely different methods to achieve it, it's Opposites Attract. If they want different things entirely, it's a divorce waiting to happen.

If you add a third-party mediator for balance, you get a Trio.

Contrast Birds of a Feather.

Popular Opposites Attract dynamics include:

Examples of Opposites Attract include:

IMPORTANT: Please, no ships, just Canon portrayal of attraction. If you see an example that hasn't been portrayed in canon as this type of attraction (or hasn't been portrayed in canon at all), please delete it. This also means examples will tend to be spoilery, so read on at your own risk.

Anime and Manga

Genki, ditzy, ignorant Usagi is with cool, calm, intelligent Mamoru in Sailor Moon.
Shikamaru and Temari from Naruto; he's lazy, calm and prone to doubting himself, she's an aggressive Action Girl (this one is not quite official, but alluded to very heavily). Also Hinata is attracted to Naruto even though she's a stuttering Shrinking Violet with nil self-confidence and he's a loud, overly-optimistic Idiot Hero. Minato and Kushina, the former being very a nice and polite man and the latter being a hot-blooded tomboy. Averted in Naruto's attraction to Sakura; while their abilities as ninja are in stark contrast, her over-the-top Tsundere temperament often exceeds even his.
The Official Couple of Monkey High - Haruna is The Ojou and used to dealing with high-class folks (her father is a now-disgraced politician), while Macharu is The Fool and very much from working-class roots (his parents run a grocery store).
In Kanamemo, no chance is spared to show the loving bond between sparkly Yume and quiet Yuuki.
Revy and Rock of Black Lagoon. She's an Axe Crazy Broken Bird and Trigger Happy Nietzsche Wannabe, among other things. He's a Non-Action Guy, a Wide-Eyed Idealist (he never gets completely disillusioned, and he has every right to), and he's the closest a series this cynical will allow to The Messiah. The sparks flying could power a medium-sized country.
Ship Tease aside, it may as well be Zelgadis the cynical, weary, brooding chimera paired with Amelia the optomistic, innocent, and plucky princess from Slayers, with hints of Brooding Boy, Gentle Girl peppered in there. In the novels, there is also the hot-headed, driven Luke with the snarky, calm Millina (in this case, this is All Love Is Unrequited).
Parodied in Sayonara, Zetsubou-sensei. The first episode plays romantic music when Nozomu first meets Kafuka, and text scrawls across the screen, "A man who is negative about everything; a girl who is positive about everything; a meeting that never should have happened." This gets further parody in a later episode showing Nami's first meeting with Kiri, playing the same music and displaying the message "A girl who refuses to come to school; a girl who refuses to leave school; a meeting that never should have happened."
Ouran High School Host Club's canon couple Haruhi and Tamaki. Haruhi is a Deadpan Snarker, and generally calm and collected when it comes to most things. Tamaki on the other hand is a Keet, exaggerated, and easily excitable. The series itself has a lot of Red Oni, Blue Oni non-romantic pairs in it.
Magical Girl Lyrical Nanoha has The Stoic officer Chrono and his Victorious Childhood Friend, the bubbly Bridge Bunny Amy.
Considering they form a Manzai duo this is inherent to the eventual romantic relationship between Koganei and Amasawa of The Weatherman Is My Lover.
Early in Oh My Goddess! run, Keiichi was a Chivalrous Pervert wondering what anyone would see in him, and Belldandy was something of an Ingenue. Characterization Marched On, and the two began develop some of the other's persona, so that after the "Lord of Terror" arc, and in the OVA, K1 became a Covert Pervert, and Bell began pouring on the affection nice and thick, frequently expressing her love for Keiichi. About two years after The Movie, sadly, the two were Flanderized to the point where he was afraid to make a move, and she rarely acknowledged their love.
While not officially a couple as of yet, Soul and Maka from Soul Eater are considered this. Maka is a Badass Bookworm who always follows the rules and feels the need to do everything right in order to get by. Soul, on the other hand, is a Deadpan Snarker who would rather do things his own way and tends to go against orders that anyone bothers to give him.
- Of course, this could be said about almost every Meister/Weapon team in the series.
  - This troper begs to differ. Kid and Liz both can be hysterical and serious; Kid has major OCD and Liz is a mega scardy-cat. Liz can calm down and be serious when she needs to help Kid get his act together, and when not having a panic attack, Kid is deadly serious. Tsubaki and Black*Star are both generally serious, although Black*Star is loud and obnoxious about it. Stein and Marie definitely fit this trope, but neither Ox & Harvar, Kim & Jackie, Lord Death & Spirt, nor Kilik & Pot of Fire & Pot of Thunder fits this trope.
  - Ox is very emotionally driven as opposed to Harvar who is more logical and tries not to let his emotions affect him. Kim is a major bully who often bosses around others and likes things done her way, while Jackie is more subissive and simply does what she's told. Pot of Fire and Pot of Thunder are too young for anyone to say anything about them yet.
Axis Powers Hetalia has the Official Couple of cheerful, ditzy Italy and stern, serious-minded Germany.
- Also Italy's Hot-Blooded Cool Big Sis Hungary and her ex-husband-but-still-love-interest, the straightlaced and even more stern than Germany Austria.
Although the series thrives on not' having an official couple, Hayate the Combat Butlers attraction between Hinagiku and Hayate is all but blatent, every character that interacts with them at some level knows it exists. While it also fits the Birds of a Feather dynamic, both these characters went about dealing with it in very different ways, leaving them almost complete opposites with the same backstory.
- And to further things along, the third character with a similar backstory is being built up to build a Power Trio dynamic.
Fruits Basket: Kyo, a hot-headed, tough, no manners, always wants to fight boy, and Tohru, a girl who's very sweet and kind.
Eyeshield 21: Energetic and outgoing Suzuna with Shrinking Violet Sena. More obviously, foul-mouthed Sociopathic Hero Hiruma with Mamori the Yamato Nadeshiko.
Ai no Kusabi has this as a plot point of why the highest of the high would want to be with the lowest of the low.
In Stellvia of the Universe, the aloof and stoic Akira eventually starts dating the laid-back Plucky Comic Relief Joey.
Boisterous Bruiser Colonel Kilgore Ramba Ral and quiet Lady of War Crowley Hamon in Mobile Suit Gundam. They're effectively a boyfriend/girlfriend varient on Brains and Brawn.

Comic Books

When their relationship began, Starfire and Robin (later Nightwing) were this: Robin was reserved and methodical to Starfire's passionate impulsiveness. As the trope often works in real life, they began to influence each other so that each acquired a level of the other's personality, to the point that their breakup ultimately had Nightwing making an impassioned plea for Starfire to stay and Starfire making the reasoned, logical choice to leave.
Batman and Catwoman: one is a stolid, no-nonsense upholder of the law, the other is a mischievous (but never malicious) lawbreaker. They Fight Crime (sometimes, when she's not causing it herself).
Cyclops and Phoenix of the X-Men. He's an emotionally withdrawn introvert control freak and she's ~~fire and life incarnate~~ an outgoing redhead who reads minds. He draws the attentions of at least two other hot and extrovert telepaths, which suggests there's something interesting going on behind that facade...
Runaways paired quirky genius Gert with dumb jock Chase.
The Authority has gruff, brooding, cynical Midnighter Happily Married to kind, cheerful, optimistic Apollo. Even their costumes emphasise this trope: Apollo's is white with a gold sun emblem, while Midnighter's is black with a silver crescent moon.
Peanuts features Peppermint Patty and Marcy. Peppermint Patty is extroverted and athletic but Book Dumb. Marcie is introverted and intellectual and not at all into sports. They develop a symbiotic relationship, with Peppermint Patty protecting Marcie from bullies and Marcie helping Peppermint Patty with her studies.
Clark Kent, mild-mannered reporter and Lois Lane, determined and outgoing reporter.

Fan Works

Axis Powers Hetalia fanfic Gankona, Unnachgiebig, Unità: Like in canon, Italy is the opposite of Japan. However, despite their opposite personalities, they have a lot in common too.

"You're so kind and warm inside that cold and calculating exterior of yours. Although it may not seem like it, we have quite a bit in common. It's nice how we can bond over literature, anime, manga, fencing, food, cats, art...and so much more. Despite not seeming like it, my heart beats fast around you." He gave a fond smile. "I can't help but love that about you Kiku."

Film

Odd Couple Steed and Mrs. Peel in The Avengers 1998: he follows the rules, she doesn't. He admits that she's "just my type".
Milo Thatch and Princess Kida, she's the Native Princess who is one P r e t t y Gi rl. Then there is Mi lo Jam es Tha tch....'nuff said. It turns out they do have a surprising amount of things in common though. And they both agree that Atlantica should stay intact, though Milo technically isn’t a native.
Roger and Jessica Rabbit. "He makes me laugh."
Captain von Trapp and Maria in The Sound of Music.
The Great Race. The Great Leslie - charming male chauvinist. Maggie DuBois - militant women's libber. How can they not fall in love?
Enchanted: Both Giselle and Robert are kindred spirits (they’re both deeply compassionate), but Giselle is initially naive and Robert is initially cynical. Fortunately, they both learn from each other…so much so they ended up getting married.
Tangled gives us the jaded, worldly-wise thief and the spirited, innocent princess.
WALL-E has The Woobie Wall-E and Action Girl EVE. Both were built for a similar purpose, however. And they find out that they have surprising amount of things in common. Still, EVE is able to explain to Wall-E that they are in a bad situation when he assumes otherwise…and he finds himself agreeing.

Literature

Ron and Hermione of Harry Potter's Power Trio: She's uptight, smart, logical and Crazy Prepared, while he's more laid back, driven by emotion and acts on instinct.
Nick Carraway and Jordan Baker in The Great Gatsby. He Will Not Tell a Lie; she's a Consummate Liar.
Luke Skywalker and Mara Jade. Mara even says it, for crying out loud!
Brainy ambitious women regularly find PG Wodehouse's Upper Class Twit Bertie Wooster romantically irresistible.
Kenneth Oppel's Airborn series has Matt Cruse, poor cabin boy, and Kate de Vries, rich wanna-be scientist... cue angsting about how they can never be together...
This seems to be the driving force behind Zavahl's and Ailie's relationship in the Shadowleague books- he has the personality of a bad rainstorm, whereas she is never seen to frown.
From The Wheel of Time, Mat is a Farmboy turned Four-Star Badass raised in a Arcadia, Tuon is a Empress and Chessmaster who was raised in a Deadly Decadent Court. They're married.
The 39 Clues. Ian is a Handsome Devil, mega-rich, an Evil Brit, and a Momma's Boy. Amy is a Shrinking Violet, pretty smart, poor, and an orphan. She apparently always found him attractive, but when he actually started flirting with her, it was, of course, a trick. And then came a whole new set of complications.
- Also, Hamilton and Sinead was hinted a bit in Book 10.
Discworld:
- Captains Carrot Ironfounderson and Angua von Uberwald are on opposite ends of the Sliding Scale of Cynicism Versus Idealism. He inspires her to fight injustice, she reminds him not to set his expectations too high.
- Similarly, in Interesting Times, it's strongly suggested that Wide-Eyed Idealist Twoflower's daughter Pretty Butterfly inherited her Rincewindian view of the world from her late mother.
In Death: Eve has pointed out that Roarke and her have this between them, like in Divided In Death. She is a cop who is crude, rude, not interested in money, believes in the law, and has morals that are basically black and white. He is a former thief who is suave, charming, has more money than you can imagine, believe more in his conscience than in the law, and his morals are very much grey. Fortunately, one thing they do have in common is that they both were raised by bad parents and had lousy childhoods.
Enforced in the novel Youth in Sexual Ecstasy, the sexual therapist actually says that for a couple to succeed in the long term, they must have opposite temperaments alongside with similar lifestyles and independent realization. The protagonist and his fiance agree on this being the case for them.
In Michael Flynn's Up Jim River, Greystroke says that he and Bridget have this.

Live-Action TV

Laid-back, jovial "Hawkeye" Pierce and hard-nosed Margaret Houlihan in M*A*S*H.
Penny and Leonard on The Big Bang Theory are such an extreme example as to nearly defy belief. Leonard is chubby, bespectacled, hopeless nerd with a Ph.D in Physics and alarmingly subpar social skills (which suddenly appear impressive when compared with those of the people he hangs out with); Penny is an attractive aspiring actress who works as a waitress in the nearby Cheesecake Factory and never finished college. Lots of Lampshade Hanging on this one.

Leonard: Are you even listening to me?
Sheldon: Yes. "Blah blah, hopeless Penny delusion, blah blah."

Badass Action Girl Aeryn Sun of Farscape, for some reason, finds herself falling for Plucky Comic Relief who alternates between The Kirk and The McCoy in the form of John Crichton. Though he's pretty well helpless in a real battle, she does end up training him up almost to Badass Bookworm levels. And while she does thaw a bit from her Ice Queen demeanor, he just gets more and more extroverted as he slowly goes crazier.
Microsoap used and deconstructed it. As the kids describe it, "It was a case of Opposites Attract. Then it was a case of Opposites Drive Each Other Crazy".
Mulder and Scully: Skeptical, scientifically oriented redheaded Catholic meets agnostic UFO/supernatural enthusiast. And it works.
Ultra-conservative Alex P. Keaton finds himself attracted to women who are the ideological opposite of him - while his best friend, Skippy, is the intellectual opposite of him.
Degrassi has done this for just about every pairing and friendship it can. It'd be faster to list the exceptions.
Moonlighting, starring Cybill Shepherd and Bruce Willis. Maddie (Shepherd) is a chic, smart, former supermodel who's dead serious about running the business; David (Willis) is a glib, lighthearted, and pragmatic Private Investigator.
The show Dharma and Greg revolves around this trope. Dharma is a free-spirited, tolerant, and ditzy flower child. While Greg is an upright, conservative, somewhat uptight lawyer. Despite the fact that they have virtually nothing in common they got married on their first date.
iCarly: Subverted or Inverted with the Sam/Fredde arc depending on what aspect you look at. The subversion is they are complete and total opposites that become physically attracted to each other but eventually break up when the actual relationship fails. They are unable to find any common ground in their interests and actually end up sabotaging them for each other when they try being involved in each other's activities. It ends up being one of the main causes of their break up. The inversion is Sam wants someone abnormal like her, and Freddie wants someone more normal like him, so that while they did have an Opposites Attract vibe, it's not what they need in a partner, making it clear that in their case they are attracted by similarity not opposition.
Bones has the coldly intelligent, scientific, atheist, hyper-rational titular character and her partner the FBI agent- religious, more emotional, more of a people person. Clearly they complement each other, but each also finds the other fascinating and attractive.
Action Girl/Hot Amazon Zoe in Firefly is married to Non-Action Guy/Ace Pilot Wash.
CSI: NY City boy Danny Messer and country girl wife Lindsay "Montana" Messer. (she's still tough in her own right, though.)
Jerk with a Heart of Gold Arthur and Shrinking Violet (except when she's sufficiently ticked-off) Guinevere from Merlin. Also noteworthy was their difference in class status, with him being a prince and she being a servant.
Parks and Recreation: Who'd have thought a liberal feminist vegetarian community college professor would be hot for the carnivorous libertarian man's-man Ron Swanson?
Buffy the Vampire Slayer is built on this. Cordelia and Xander, Willow and Oz, Faith and Xander, Giles and Jenny, Giles and Joyce, Buffy and Faith, Faith and Angel, Willow and Tara, Buffy and Spike, William and Drusilia, Faith and Wood, and there's likely several others unmentioned.

Music

You Lost My Memory by Skyclad. This romance doesn't end well, but is described as sort of awesome anyway.

The Brownian-Motion within this love potion,
ensures our opinions are always dividing.

The Paula Abdul song "Opposites Attract" is basically all about this trope. And the music video involves her singing it as a duet with an animated rapping cat...
The song also called "Opposites Attract" by Juris.

Video Games

BioWare has a tendency to create somewhat psychotic mad people (usually women) who can be most successfully romanced by a nicer player character.
- Jack in Mass Effect 2 is impulsive, impatient, anger-driven, and generally insane; the Paragon romance arc involves calmly and patiently listening to her issues and generally being nice.
- Morrigan in Dragon Age is a survivalist in the extreme who believes love is a weakness; she does, however, approve of some of the Warden's behavior that is rather contrary to her stated doctrine.
- Garrus in Mass Effect 2 has trouble with the rules, but is just as likely to fall for Female!Shepard if she calls him out on it and points out that the rules are there for good reasons as if she goes along with his ends justify the means ideas.
- Bastila in Knights of the Old Republic is attracted to the male player character no matter what, so if you are a silly rule-bending sort or an Ax Crazy maniac your very straight-laced and overly serious companion will still fall for you.
In Fire Emblem Elibe we have Fiora (serious, motherly Pegasus Knight) and Sain (Chivalrous Pervert who mouths off to authority). And if you max out their supports, they get married.
- also Fiora's Tsundere and Hot-Blooded middle sister Farina and Sain's partner Kent. Yup, they can get hitched at A support level too. They even hang a huge lampshade on this:

Farina: “This is probably someone else's doing... Like Marcus, or Oswin... You know, Merlinus might try something like this, too...”
Kent: “I don't think it is a conspiracy... I mean, what would anyone have to gain from making us fight together?”

The Forerunners Didact and Librarian from Halo. The Librarian is a Friend to All Living Things whose favorite species was humanity. The Didact is a Four-Star Badass in a society of pacifists, who was responsible for destroying humanity's empire and sending us back to earth as cavemen. Everyone lampshades how odd this match is; however, they both love each other fiercely.

Bornstellar: Your relationship with the Lifeshaper does not seem ideal
Didact: You don't know the half of it.

Web Comics

Averted in Slightly Damned. The main pairing is Kieri, a water-elemental angel, and Buwaro, a fire demon. Seems like a perfect setup for this trope...but in terms of personality, they're really very similar.
In Dubious Company, Walter is an Educated, Goofy, Sky Pirate Bird Man. Tiren is a Hardened, Straight-laced, Ninja Catgirl. Clearly, the crew knows they were made for each other. Except Mary, who insists that Tiren has eyes for Elator.
Homestuck: Vriska Serket and Tavros Nitram, as well as Vriska and John.
Questionable Content: Hannelore's parents - her father is a goofy Mad Scientist, and her mother is a calculating, dispassionate supervillain.
L's Empire has Carnation and Pix who are pure evil and pure good respectively.

Web Original

Mille and Iriana of Ilivais X. Iriana is a Broken Bird Creepy Child who acts like an Emotionless Girl to avoid her Drive Core pushing her towards being a hyper Love Freak, and is highly logical and cynical, yet becomes surprisingly impassioned and devoted when those she cares about are in danger. Mille is essentially a blank slate Phonos Weapon in the form of a cheerful, lively, and outgoing Ethical Slut who's a little on the ditzy side and erratically emotional, but take Iriana from her and she becomes dark and sullen. They couldn't be more opposite, and they couldn't be crazier about each other.

Western Animation

Robin and Starfire on Teen Titans. Robin is the serious, determined leader, and Starfire is the sensitive, sunny one. However, both are highly intelligent…Starfire happens to enjoy learning about Earth from Robin. And both are deeply compassionate. And while Robin has rescued Starfire in the past, she is far from ungrateful and has done the same.
Rogue's attraction to Scott in X-Men: Evolution, at least until you think about it for a while. But on the surface, he is The Stoic and she is The Snark Knight.
Silverbolt and Blackarachnia of Transformers Beast Wars fit this trope without Question: Femme Fatale and Knight in Shining Armor.
Miss Information and Mr. Smartypants on Histeria!: The Dumb Blonde and The Smart Guy.
Kim Possible and Ron Stoppable Who do eventually hook up. The first one is a popular overachiever, the second one is a unpopular underachiever.
Exaggerated in Kids Next Door with Kuki Sanban (Numbuh 3) and Wallabee Beatles (Numbuh 4). He's an abrasive Blood Knight with an extreme aversion to everything cutesy and sugary, while she's an upbeat and extremely sweet Japanese girl with an obsession for stuffed animals. In the series' Distant Finale they get married.
- A lesser example would be Hoagie Gilligan (Numbuh 2) and Abigail Lincoln (Numbuh 5). He's a Gadgeteer Genius Non Action Guy who likes to tell awful jokes, she's a snarky Action Girl who serves as the voice of reason. They got married too in that same finale.
- Deconstructed with Nigel Uno (Numbuh One) and his girlfriend Lizzie Devine. Their relationship is clearly imbalanced due to his extreme devotion to the KND and her incredibly obsessive attitude. Predictably enough, this leads to them ultimately breaking up near the end of the series.

Real Life

Actual science tends to show that the best predictor of compatibility is in fact similar background, interests, and attitudes. A likely reason is that we tend to only notice the ways a couple are different (since it's not that surprising when two partners are alike), at which point we feel the need to form a theory to explain why all the couples we see are so different (when they are, in fact, Not So Different). The grain of truth in it is that a partner who's exactly like you in every way would probably cause all sorts of problems, so we do seek our opposites, after a fashion—just not our total opposites.
SPC Kate Norley, an activist representing Vets For Freedom, a group whose "mission is to educate the American public about the importance of achieving success in [Iraq and Afghanistan]," and still an occasional guest commentator on Fox News, while attending the 2008 RNC convention to show her support for John McCain, as part of a campaign that earned her praise from right-wing bloggers up to and including Michelle Malkin, apparently fell in love with one of the correspondents there. They're now engaged, and they expect to marry sometime 2011. His name? John Oliver.
Roger Ebert and Gene Siskel. For example, Roger Ebert hated Mars Attacks! because Tim Burton "seemed to like the aliens more than the humans" (paraphrasing); Gene Siskel loved it for the exact same reason. Even in watching old At the Movies episodes, you can tell that Siskel is more carefree and cheery, while Roger Ebert is ever-sarcastic and snarky.
- The biggest case of this is perhaps their disparate views on Blue Velvet. Ebert notoriously hated it and found the scene with Isabella Rosselini standing naked on Kyle MacLachlan's lawn to be misogynistic, while Gene Siskel loved it and compared it to Psycho.